Without the health of the townspeople, there is no recovery. Without the peace of mind of the townspeople, there is no recovery. However, we appreciate that the situation is very complicated and that everybody has their own viewpoint.
While some may agree with the need for decontamination work, others may see it as costly and potentially ineffective. At the same time, others welcome the decontamination activities but may feel frustrated by the current pace and want to see the work somehow speeded up. The nuclear accident at Fukushima has had a terrible cost for Japanese society and particularly for those living in the contaminated areas.
It has been divisive, splitting communities and families with regards to how they deal with the contamination and whether or not they choose to stay in Fukushima.
One very important point is to try to see the problems associated with the accident and subsequent cleanup from all sides, particularly from the view of those living in Fukushima. The video we made with the MoE is just one side of this story. The main message is that we all need to learn from this accident and its aftermath. It is essential that we work to ensure it never happens again. We arrive at the cleanup site and put on our masks. Photo: Stephan Schmidt. Huge vacuum cleaner-type machine sucking up radioactive materials.
Photo: Brendan Barrett. Removed soil and materials are placed in blue plastic containers. Waste is stored temporarily on the baseball field. Passing through the police checkpoint on the way out.
The views expressed in this article are those of the author and do not represent the views of the United Nations University nor the Ministry of the Environment of Japan. An IRID official in charge said it will do its best so that there will be minimal effect on the entire schedule.
Significantly high radiation levels inside the reactor No. Even though the robotic device is designed to tolerate a certain level of radiation, engineers still need to control it accurately while racing against time before the device malfunctions under the high radiation. Moving a couple of centimeters in the wrong direction could be fatal for the mission at hand. Training is essential for this kind of sensitive work.
But with the pandemic, there is no telling when engineers from the U. Inside reactor No. While Tepco plans to use the robotic arm to retrieve fuel debris from the containment vessel, it needs to come up with another way to clear the debris inside the pressure vessel, planning everything from scratch. At present, nothing has been decided. If engineers take out the debris from the bottom of the pressure vessel, the debris itself as well as other parts inside may fall to the bottom of the containment vessel, and that could damage other devices.
Since that could become another headache on its own, some sources believe it is not realistic. If they want to take out the debris from the side or from above the pressure vessel, they need to create a hole in the vessel to put through a device to see what it looks like inside. In order to do that, though, they need to retrieve spent nuclear fuel placed in a pool located at the top of the reactor building.
The plan is to start removing the spent fuel rods in reactor No. At reactor No. Research up to present shows that the inside of the vessel has drastically changed from its original state, with fuel debris tangled up with structural parts piled up to three meters high at the bottom of the containment vessel. Researchers are analyzing how to remove the debris. In March, Tepco revealed a roadmap for decommissioning the Fukushima plant over the next 12 years, with a plan to remove the debris from reactor No.
It also laid out a plan to lower the water level for reactor No. The water level is above the ceiling of the ground floor of the reactor building, which is more than the amount of water at reactors Nos.
In order to apply the same tactics used to remove reactor No. Tepco plans to draw out water through the suppression chamber connected to the bottom of the containment vessel. But at the same time, Tepco needs to inject water to cool the fuel debris, which means it needs to adjust the amount of water injected and drawn out.
One of the headaches is that the suppression chamber is filled to the brim with water. That is putting more pressure on its walls than expected, causing it to deteriorate more quickly. Anti-earthquake measures also need to be installed. A Tepco employee gives a lecture in front of the No. If the fuel debris is no longer underwater, which shields engineers from radiation, it is expected to be harder for them to retrieve it. Tepco is also concerned about the possible rise in radiation levels and dust laced with radioactive materials floating inside the containment vessel.
JAEA research shows that, judging from the temperature and other conditions, the half-melted fuel debris fell off slowly, leaving the possibility that there still may be something that could trigger a chemical reaction. The radioactive remains of the reactor buildings are, however, still off limits.
But areas underground beneath the plant remain extremely hazardous. Radioactive cooling water is leaking from the melted-down reactors and mixing with groundwater. The groundwater then must be pumped out to keep it from leaking into the sea.
Other contaminated water — some of which was initially sprayed and dumped on the reactors while they were melting down — sit in other underground locations, leaking continuously into groundwater outside the plant.
Tepco has attempted to remove most radionuclides — like cesium and strontium — from the excess water, but the technology does not exist to cleanse it of tritium, a radioactive isotope of hydrogen. Coastal nuclear plants commonly dump water that contains tritium, which occurs naturally in nature, and Japanese officials insist it is harmless when ingested in small quantities. So the accuracy of the data before any release is crucial and must be verified.
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